The approaches described in this section could be pursued, but are not necessarily approaches that have been previously conceived or pursued. Therefore, unless otherwise indicated herein, the approaches described in this section are not prior art to the claims in this application and are not admitted to be prior art by inclusion in this section.
Data communication networks may comprise a hierarchy of nodes that may each receive, process, and send unbounded, streaming data. A data stream may include a large amount of data per second. Furthermore, when a node in the network, which takes data from the input data stream as input, is suspended, intentionally or unintentionally, the node may lose input data while the node is suspended. Further still, in some cases multiple data streams may be received simultaneously.
Some systems may attempt to distribute processing of a data stream query across nodes within a network. An administrator may increase or decrease the number of nodes processing the query by stopping all processing across all the nodes, increasing the number of nodes, and subsequently restarting all the nodes. Stopping and starting nodes can be time consuming. Thus, data in the input streams may be missed while an administrator attempts to increase or decrease the number of nodes processing a data stream.